The synthesis and characterization of several unique reagents and probes for biological studies are proposed. Specifically, we describe a) a new class of detergents which are chemically or photochemically destructible at the desired time, thus aiding their complete removal for reconstitution studies of membrane proteins; b) two new types of intracellular (or intravesicle) molecular pH meters designed to aid studies of proton gradients across biological membranes; c) a new series of crown ether, cryptate or complexone molecules designed to measure specifically intracellular (or intravesicle) activities of Na, K and Ca2 ions; d) several new highly electron dense "small" molecules designed for high resolution electron microscope studies of cell surfaces. The significance of this research is to make available for the first time new molecules which have been designed to overcome at least some of the currently serious obstacles frequently encountered in fundamental research on how cells function.